Electric switch



Aug. 6, 1929.

R,-w. ARMSTRONG ETAL v 1,723,758

ELECTRIC SWITCH Filed Sept. 20, 1926 2 Sheets-Sheet IN V EN TOR. IRA E. M CABE m0 RAYMOND WAHMSTRONG 11 A TTORNEYS.

1929- R. w. ARMSTRONG ET AL ELECTRIC SWITCH Filed Sept. 20, 1926 2 Sheets-Sheet 2 IN V EN TOR. 7

[RA ELM- OABE no RAYMOND WARM$7R0N5 M TTORNEYS.

Patented Aug. 6, 1929.

UNITED STATES 1,723,758 PATENT OFFICE.

RAYMOND W. ARMSTI RONG AND INA E.- MCCABE, OF CHICAGO, ILLINOIS; SAID ARM- STRONG ASSIGNOR- TO THE ARCLESS CONTACT COMPANY, A CORPORATION OF ILLI- N OIS.

ELECTRIC SWITCH.

Application filed September 20, 1926. Serial No. 136,503.

This invention relates to improvements in electric switches and more particularly to a mercury tube type light-operated switch.

It is an object of this invention to provide a switch of this general character having two enlarged sealedend portions joined at an angle toeach other by restricted V-shaped connecting portion having a mercury seal therein with means for supporting electrodes or terminals in the walls of the V-shaped portion and to provide 's light absorbing medium within one of the enlarged end portions whereby the body of the switch proper may be formed integrally and of the same charactor of glass or other transparent material. The advantages of this inventioii-arein the construction of the switch body providing a uniform and simple method for supporting the electrodes therein, whereby the leads may be attached to the lower side of the switch and the light absorbing medium of desired character positioned within one bulb or enlarged end portion before sealing so that the body may be formed integrally of the same character of glass or other media whereby subjecting the switch to light, heat, or chan e in temperature will affect both bulbs similar y and increase or decrease, the internal pressure equally, except when subjected to the light rays the enclosed media is adapted to absorb, furthermore, such media being within the sealed bulb, none of its increase in temperature is dissipated in surrounding atmosphere and the operation of the switch' is more sensitive than when the absorbing medium forms a wall, also by forming the absorbing medium of irregular particles, a greater absorb ing surface is presented to the action of the light rays. 7

.While the preferred forms of this invention are illustrated upon the accompanying sheets of drawing, yet it is to be understood that minor detail changes may be made without departing from the scope therein.

In the drawing:

Fig. 1 is a view in front elevation of one form of this invention, looking into the open side of the switch casing. V

Figure 2 is a similar view illustrating the switch parts in central transverse vertical section, showing the absorbing medium in side elevation. V

Figure 3 is a view similar to Figure2 of a modification. r

of the connecting tubular the rear wall of a cylindrical casing 4 by clips.

5 attached thereto and engaging each bulb. The rear casing wall also supports binding posts 6 and 7 connected to the respective I switch terminals by leads 8, which binding posts may extend through the casing wall to provide exterior connections to the circuit to be controlled.

It is preferable to construct the legs of the V-shaped connecting portion in tubular form extending from each bulb and in alignment with the center line thereof with the adja equally distant from their respective bulbs and one leg extending beyond its connection with the outer wall of the other leg, which leg is formed with a well of similar diameter and extending parallelto the first leg and having a right angular closure 10, formed in the lower wall adjacent its juncture to the bulb of such proportions that the juncture of this well on the lower side with the connecting portion is slightly above the apex formed by the joining of the adjacent walls portion 3. Through the closures 9 and 10 of bothof the Vfand well, adjacent one bulb, electrodes 11 are passed and centrally secured therein by scaling in a tubular portion of the closure material. The leads 8 to the binding posts are respectively attached to the exterior portions of the electrodes 11. Sufiicient quantity of electric conducting fluid 12, such as u mercury, is inserted in the device before sealing to form a liquid'seal between the bulbs 1 and 2 in the'V-shaped connecting portion 3 and fill the well extending from one leg thereof which, by its construction, is separated from the main body of the seal so that under normal conditions, the circuit through binding posts 7 and 8 is open and-the interior pressure within the two bulbs is equal. Upon an increase in pressure in bulb 2 the liquid seal will be caused to move upward cent walls of the V adjoining each other in the leg extending from bulb 1 and join the liquid in the adjacent well, closing the electric connection between the electrodes 11. Upon excessive pressure being created within bulb 2, the expanding gas therein will pass through the liquid seal in bubbles without breaking the electric counectionand as the pressure in the two bulbs equalizes inre turning to normal, the excessive gas will bubble back through the liquid seal to its original container.

This construction not onlytallows the electrodes 11 of the switch to be connected to the binding posts leads 8 upon the underside of the device,'but-1by the formation of the parallel walls having the parallel closures 9 and 10, facilitates the insertion and sealing of the said electrodes 11, and, furthermore, the provision of the well containing the electrode adjacent the bulb submerges that electrode in the conducting'fiuid and separates it under normal conditions but a short distance from the main body thereof so that a slight movement of the main body of the conducting fluid seal willmake or break the electrical connection between the electrodes 11 and the electrodes both being submerged in the conducting fluid after contact has once been made, the passing of gas through the conductingfiuid will not afl'ect such connection.

As above stated, this device is a light-operated switch and as such is provided with means causing the actuation thereof when subjected to the rays of light. In the forms shown this means is enclosed in bulb 2 and when subjected to the rays of light increases the pressure of the gas enclosed in that bulb causing the liquid-seal to be forced upward in the leg extending from bulb 1 and close the connection between the two electrodes and upon the removal of thesource of. the light rays, the pressure in the two bulbs is equalized causing the liquid seal to resume its original position, thereby breaking the connection between the electrodes.

It is recognized that bodies, when subjected to light, either absorb, reflect, or transmit the rays of light falling upon their surfaces in accordance with their composition, also most transparent bodies, such as glass, whileture of the gas-enclosed in one of the bulbs of a switch of the character above described is not broadlywtlaime'd as part of this invenhe Switch willffuncljionimol'e p y- F g- .lar switch construction.

contemplate the specific location of such light ray absorbing medium in this particu- Referring to Figures 1 and 2, the bulb 2 is shown with a smaller bulb 14 inserted therein before the enclosing bulb is sealed, the enclosed bulb 14 having an enlarged opening at the bottom with the edges resting upon the inclining walls of the enclosing bulb. This enclosed bulb 14 is formedof a media adapted to absorb the rays of the visible spectrum, such as colored glass, and in so doing, the energy of the absorbed rays are transmuted or converted into heat which increases to produce its color, and in so doing, increase the internal pressure within the enclosed bulb 2 and move the mercur-yseal 12 upward in the other leg of the connecting portion to close the circuit through theterminals 11 and upon removal of the source of light, the

' increased temperature of the gas within the enclosed bulb 2. will be transmitted through the conductivity of its walls to the surrounding atmosphere until the pressures in 'both bulbs 1 and 2 equalize, move the seal back to normal, and open the circuit between the terminals 11. Hit is desired to construct the switch to normally close the circuit and to operate to open the circuit when subjected to visible light, the bulb 14 or like absorbing media is enclosed in bulb 1 and before sealing sufficient mercury 12 is inserted in'the V-shaped connecting portion 3, so that the level of the mercury in both legs is above the i opening of the well adjoining bulb l, or-with the amount of mercury 12 remaining the same as shown, the pressure in bulb 1, after the insertion of bulb 14, is reduced suflicient- 1y before sealing to allow the seal to normal- 1y cover the opening of the adjacent well, thereby normally closing the circuit between the electrodes 11. Then upon subjecting the bulb to the rays of visible light, the heat in the walls of the bulb 14 will increase the pressure in bulb 1 and move the seal away rom the adjacent well and open the circuit between the electrodes 11.

- It has been found that if the light absorbing medium, such as colored glass, be in the formof irregular particles, instead of symmetrical bulb 14, shown in Figures 1 and 2,

ure 8 illustrates such a construction in which parts similar to those shown in Figure 1 or 2 are indicated by similar reference numerals. In this case, the absorbing medium is composed of a plurality of irregular pieces of flat colored glass 15 brbken into sections of such size that they may be readily inserted into bulb 2 before sealing and substantially fill the bulb from wall to wall above its contracted portion where it joins the restricted connecting portion 3. A greater surface of absorbing medium is exposed to the action of the rays of visible light than in the form shown in Figures 1 and 2, and the gas enclosed above the seal in bulb 2 filling the interstices between the particles of the absorbing medium is more readily heated and expanded when such medium is subjected to visible light, and therefore, the switch will operate to close the circuit more rapidly than in the other form, as the increase in temperature of each portion of each absorbing particle upon which the visible rays fall is conducted to the remainder of such particle and transmitted to the surrounding gas.

The insertion of the light absorbing medium into the interior of one bulb of the device, as shown, makes it possible to form both bulbs and connecting portion integrally by drawing or otherwise forming the parts of glass or other desired media thereby obviating the necessity of forming one bulb of another character of glass and welding or otherwise joining to the body which may possess different co-eflicients of absorption or expansion. Such a device may be formed integrally in less time and with less danger of breakage than where another part must be welded Or joined thereto and in service the danger of a rupture at the joint of two parts is overcome.

By the proper selection of the transparent medium for forming the device proper and the light rays absorbing medium contained therein, variations in the operation of the switch may be produced.

What we claim is:

1. In a light operated electric switch, two interconnected transparent containers, an electric conducting fluid seal therebetween, electrodes entering within the connecting portion adapted to be connected and disconnected by the fluid seal, and a medium adapted to absorb the rays of light supported by the walls of one container and enclosed above the liquid seal in that container, whereby, when the switch is subjected to light, rays thereof are transmitted to the absorbing medium and increase the temperature and pressure in that container to move the liquid seal to connect or disconnect the electrodes.

2. In a light-operated electric switch, two interconnected sealed transparent gas containers, an electric conducting fluid seal therebetween, electrodes entering within the connecting portion adapted to be connected and disconnected by the fluid seal and a plurality or" contacting particles of a medium adapted to absorb rays of light enclosed above the liquid seal in one container.

3. In a light-operated electric switch, two transparent gas containers having a restrict ed connecting portion communicating with the interiors thereof, an electric conducting fluid seal therein, electrodes entering within the connecting portion adapted to be connected and disconnected by the fluid seal and a medium adapted to absorb rays of light enclosed and supported by the walls of one container above the liquid seal in that container.

4. In a light-operated electric switch, two transparent containers having a restricted connecting portion connecting the interior thereof, an electric conduct-ing'liquid seal therein, said connecting portion provided with a well adjacent one container adapted to be filled with a portion of the electric conducting liquid normally separated from the remaining portion, an electrode entering within the well and submerge in the conducting liquid therein, an electrode entering within the connecting portion and submerged in the separated conducting liquid, and a medium adapted to absorb rays of light enclosed above the liquid seal in the container most distant to the well, whereby when the switch is subjected to light rays thereof are transmuted by the absorbing medium to increase the temperature and pressure in the enclosing container to move the liquid seal to contact with the liquid in the well and thereby close the electric circuit between the electrodes.

RAYMOND WV. ARMSTRONG. IRA E. MCCABE. 

